The present invention relates to a winding stair which comprises a newel post having elongated slots around the periphery at different elevations and screw holes corresponding to the elongated slots, a plurality of steps respectively hooked in the elongated slots and then fixedly secured to the screw holes by screws, and a plurality of balusters respectively fastened to respective through holes at the steps far from the newel post to support a step and a handrail, if any, above the steps.
Regular winding stairs are commonly comprised of a newel post, a plurality of flat, conical steps (about ten to twelve pieces) mounted around the newel post, a handrail, and a plurality of balusters connected between the steps and the handrail. Each step has a shorter end made with a mounting ring for coupling to the newel post, and a broader end made with two through holes for mounting a respective baluster. The balusters are respectively inserted through the through holes of the steps, each having a bottom end fixedly secured to the floor and a top end fixedly connected to the handrail. During the installation, the mounting rings of the steps are respectively sleeved onto the newel post, then respectively adjusted to the desired angles, and then fixedly secured at the desired angles. Because the steps are heavy (each step weights about 10 kgs), it is difficult to fixedly secure the steps at the desired angles. Furthermore, because the steps are fastened to the newel post by the respective mounting rings, they tend to vibrate or slip from place when they bear an excessive weight.